speed 1ms-1. She then returns from B to A along the same road with an average speed 2ms-1. Find the average speed of the girl for the whole journey.
Answer: 1.33ms-1
更新1:
Answer: 1.33ms-1 !!!!!!!!
Physics HKCEE 2001 (2)
2007-02-22 11:52 pm
A girl walks along a straight road from a point A to a point B with an average
speed 1ms-1. She then returns from B to A along the same road with an average speed 2ms-1. Find the average speed of the girl for the whole journey.
Answer: 1.33ms-1
speed 1ms-1. She then returns from B to A along the same road with an average speed 2ms-1. Find the average speed of the girl for the whole journey.
Answer: 1.33ms-1
回答 (2)
2007-02-23 12:58 am
✔ 最佳答案
Average speed is [distance / time]= 2xAB / (AB/1 + AB/2)
=2AB/(3AB/2)
=4AB/3AB
=1.333333
Because total distance is 2x AB
the total time used is (AB / 1) and (AB / 2)
2007-02-22 11:57 pm
(1ms + 2ms) /2 =1.5MS
收錄日期: 2021-05-03 05:11:26
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